1. A coarse-grained igneous rock composed almost entirely of plagioclase feldspar, typically light-colored and found in the Moon's highlands and in some terrestrial formations.
Usage: geology; technical

Examples

• Anorthosite samples collected from the Moon's surface revealed the composition of ancient lunar highlands.
• The geologist identified anorthosite in the rock formation based on its high feldspar content.
• Anorthosite is one of the most abundant rock types found on the lunar surface.
• The light-colored anorthosite contrasts sharply with the darker basaltic rocks in the region.
• Scientists study anorthosite to understand the early history of the Moon's crust.